A
closer look at the movement
(pic#1)
Overview of the completely disassembled movement. Cleaned and ready for
assembly. Movement screws on the top right hand side and dial screws on
the top left next to the mainspring.
(pic#2)
A close up of the barrel, mainspring and barrel arbor. Like the ETA
2892, and most modern movements today, Rolex also use the micro-gear
toothing throughout the movement, including the barrel and both the
movement and dial trains.
(pic#3)
A comparison of the shorter ETA 2892 mainspring compared to the much
longer one of the 3135. This longer mainspring enables Rolex to squeeze
a 50 hour power reserve out of the latter. Although the 2892 mainspring
is both lower in height and shorter, it is marginally thicker – i.e.
slightly stronger.
(pic#4) A
size comparison between the rhodium plated 2892 barrel and the plain
uncoated brass barrel of the 3135.
(pic#5) The
mainspring fitted into the barrel, ready to be lubricated and then
closed up with the cover.
(pic#6)
The 3 glucydur train wheels, plus the escape wheel and pallet fork.
Note that although the teeth and pinion leaves of the wheels are
different sizes in order to facilitate the power reduction from the
barrel to the escapement, the diameter for the various wheels,
excluding the escape wheel, are almost identical.
(pic#7) The
movement side of the rhodium plated stamped brass main plate. IWC
nickel palte
theirs. Other manufacturers, like Lange & Sohne, who use nickel
silver instead of brass, don’t plate their main plates at all.
Note
the beryllium bronze bushing in the center for the canon pinion, and
the two brass nuts near the top. The latter two facilitate quick minor
adjustment of the end shake of the balance wheel.
(pic#8) The
canon pinion placed in position.
(pic#9)
And fitted with its own separate bridge. The jewel in the center of
this bridge supports the second wheel and not the canon pinion, as the
latter is supported by beryllium bronze bushings both at the top and
bottom. It’s interesting to note that like the JLC 889, the canon
pinion is driven directly by the barrel. This arrangement provides
maximum torque in order to drive the dial and calendar train wheels,
but is not part of the drive train.
(pic#10)
A clear view of the layout of the drive train wheels without the bridge
in place. Fitted adjacent to the stem and crown are the crown wheel,
stop lever and crown wheel bridge. This system is unusual in that the
not only is the crown wheel under the bridge (a practice usually
implemented in very thin watches), but it also has its own separate
bridge.
(pic#11)
And with the bridge in place.
(pic#12)
The complete movement minus the balance wheel. The winding and wig-wag
wheels on the right hand side of the brass ratchet winding wheel
facilitate hand winding. The wig-wag swings easily out of the way when
the automatic winding system is engaged.
(pic#13)
And with the balance wheel installed. Its diameter is approximately
10mm, about the same size as that of the 7750.
(pic#14)
The dial side of the movement with stem and winding system installed,
but prior to the installation of the barrel and balance wheel.
(pic#15)
The upper half of the canon pinion, which is friction fitted to the
lower half, has been installed together with the two set wheels.
Setting of the hands is accomplished via the latter two wheels and the
sliding pinion.
(pic#16)
A clear view of the layout of the dial wheels prior to the installation
of the calendar plate. The latter supports the calendar disc as well as
keeping all of these wheels in place. On the left hand side you can see
the brass date driving wheel with its steel cam riveted to it. The
spring, lever and jewel resting up against it provide the tension and
torque necessary to effect the instantaneous date change. The shape of
this cam has been carefully calculated (together with the thickness of
the spring) in order to limit both the force applied and the amount of
travel, so that the date always jumps exactly one day. The small pin
near the 12 ‘O clock position on the cam drives the date jumper which
fits on top of it.
(pic#17)
And here with both the calendar plate and date jumper in place. At the
10’O clock position one can see the finger on the date jumper. The
latter strikes the date indicator and moves it ahead one day every 24
hours. The three domed shaped jewels equidistant in the center of the
calendar plate cut out, support the calendar disc. Doing it this way
reduces friction to a minimum and helps ensure an instantaneous date
change at midnight.
(pic#18)
For comparisons sake here’s the dial side of a caliber 3130 – i.e. no
date. Here one can clearly see the jewel inside the top part of the
canon pinion tube. As far as I know, Rolex is the only one to use a
jewel to support the upper part of the second wheel pinion like this.
The advantage of this is that it’s supported more accurately and with
less friction too. Caliber 3035 originally used a Teflon washer, but
Rolex discovered that a jewel was much better in the long term because
the Teflon eventually deformed and lost its smoothness, and this extra
friction greatly reduced the amplitude of the balance wheel.
(pic#19)
With the calendar disc installed, the dial side of the movement is now
complete and ready to be fitted with the dial and hands. The date
finger is between the 18 and the 19 a few minutes after the date has
jumped. Near the 3 and 4 of the date indicator disc is quick set date
corrector wheel.
(pic#20)
A close up of the small brass post that the set wheel sits on. The
second set wheel sits on a metal post as can be clearly seen in pic 15.
(pic#21)
A side view of this post shows how severely it can be damaged if the
movement is not serviced regularly. This is most likely to happen if
moisture gets into the watch, which was the case in this particular
instance, due to the fact that the heavier moisture displaces the
lighter lubricants.
(pic#22)
To put things in perspective for you, I photographed the 3035 and 3135
set wheels side by side. The latter is on the left, and the much larger
and more robust 3035 on the right.
(pic#23)
And a side view highlighting the differences in thickness.
(pic#24)
Overview of the automatic winding system prior to assembly. The large
wheels and simple design result in the most efficient automatic winding
system that I’m aware of. The red reversing wheels are Teflon coated in
order to reduce friction and don’t require any lubrication. Only the
posts of these wheels require a small amount of lubrication because
they are steel, as are the inner wheels that pivot on them. The small
wheel below the brass ratchet driving wheel is the winding pinion. This
fits onto the rotor axel and is driven by it. The clip at the bottom
holds the rotor in place and has a small hole on the left of it for
sharp tweezers (preferably brass), so that it can be easily unclipped
in order to remove the rotor from the automatic winding unit.
(pic#25)
The underside view of the fully assembled automatic winding unit and
rotor.
(pic#26)
And installed on the movement sans the rotor. Note the crescent shaped
bridge by the balance wheel. In case of a hard perpendicular blow to
the watch, this bridge prevents the edge of the rotor from hitting the
rim of the balance wheel.
(pic#27)
The complete movement, carefully cleaned and lubricated, ready to be
installed in the watch case. This Swiss mechanical marvel of precision
micro engineering is once again ready to offer years of accurate and
trouble free time keeping.
A few observations:
As
far as I am concerned it’s very sad that even with the huge slew of new
movements that have been introduced during the 3135’s past two decades
of continuous use and refinement, there still aren’t too many
challengers to the Rolex triple crown of accuracy, reliability and
durability – i.e. its toughness – for example, its ability to withstand
the abuse of everyday life that most active people, both men and women,
would hurl at it, and still keep on ticking. And not just keep on
ticking, but to continue doing so accurately too. The only ones that
come to mind are the ETA 2892-2A, the ETA 7750 (including their
numerous variations and incarnations) and possibly Omega’s new caliber
8500. But unlike the first two movements, the latter one,
notwithstanding the fact that it is their 3rd generation of Dr. George
Daniel’s co-axial escapement, doesn’t have the advantage of over 20
years worth of use, abuse and refinement, so it’s still an open
question as to its long term reliability. So in my opinion, that leaves
only two serious contenders to Rolex’s 3135 throne. Of course I would
be remiss not to mention Rolex’s own caliber 2235 for its ability to
match the three men’s movements. Which is an astounding achievement
given the fact that this is a lady’s movement and a lot smaller in
diameter and volume than the aforementioned ones.
Initially
I was also going to include the Zenith Caliber 400 in this small
selection above, but ultimately decided against it because although
it’s virtually on a par with the ETA 7750 in most respects,
unfortunately unlike the latter, it is only available in various
chronograph options.
I’ll
be the first to admit that none of these movements will win any prizes
for their aesthetics, or their level of decoration. Plus there are
other movements that I have mentioned before that can match these three
in terms of accuracy, but I haven’t included them here because they are
too fragile to be classified as tough movements, or haven’t been around
long enough to prove their long term reliability. A perfect example is
the JLC 889. An excellent, accurate and reliable movement when serviced
by competent watchmakers, but not known for its ability to withstand
abuse Then of course we have a few Seiko and Citizen movements that
have an outstanding reputation for their toughness and reliability, but
most of them fall short in the accuracy department, and one is
fortunate if they are accurate to better than +- 15s per day. As a note
of interest that standard was more than acceptable for certified COSC
chronometers in the 1960s, but most people today expect better, having
been spoilt by the standards of their thermo-compensated, atomic clock
adjusted quartz watches. And so the COSC have raised their standards
accordingly.
And
the winner is…
Of
these three movements which one do I like the best? If accuracy is your
only criteria, then it doesn’t matter which one you choose as there
really is virtually no difference between them in that regard. Sure
some individual movements might time out marginally better than others,
but overall the differences in time keeping between them is
insignificant. All three are capable of exemplary accuracy in all six
positions, and do so with a minimum of variation and loss to the
balance amplitude. More importantly, they should provide excellent
accuracy and reliability under real world conditions too.
As
for me, please keep in mind that no movement is perfect and that they
all have their strengths and weaknesses. Having said that though there
is absolutely no question in my mind, that I prefer the ETA 2892-2A
over the other two. Okay, so it’s been around almost half a century and
in many ways isn’t as sophisticated as the Rolex – no Breguet
hairspring, or Parachrom hairspring material etc – but during its long
lifetime in its best available chronometer version, it has proven
itself to be an exceptionally accurate, reliable and tough movement.
Its two main advantages over the 3135 are that it’s quite a bit
thinner, only 3.6mm thick versus 6mm, and has only one major weakness –
the inefficiency of its automatic winding system, as I mentioned in my
earlier review of it. While good enough for most reasonably active
folk, it is not efficient enough for those people, young or old, who
lead a sedentary lifestyle.
I
wouldn’t have any qualms about someone who preferred either of the
other two movements though. At 8mm high the 7750 is the thickest and
ugliest of the three. It also has the noisiest rotor of any automatic
watch that I have worked on, but one cannot question its accuracy,
reliability and toughness.
The
3135 is the youngest, most sophisticated and best looking of these
three and it has many admirable strengths. A longer power reserve and
instantaneous date change to name a few. As for the weaknesses of the
3135? In my honest opinion there are only two glaring weaknesses. The
first is that the oscillating weight pivots on a steel post that is
riveted to it and held in place by two jewels. The small circumference
of said post, coupled with Rolex’s simple and efficient reversing
wheels and gearing ratios, greatly improves the winding efficiency of
the automatic unit. This is probably the most efficient automatic
winding system available today. But unfortunately its tiny diameter
doesn’t give enough support to the weight to stop it from hitting
against the movement plates every time the watch is subjected to even
light perpendicular blows, let alone strong ones. I think that an
upgrade to an oscillating weight pivoting on ball bearing races, like
they’ve done in their new chronograph movement caliber 4130, is long
overdue in order to eliminate this problem. It would be even better if
they used lubrication free zirconium oxide ball bearings like JLC, PP
and others that are doing so today, not only for their strength, but
also for their efficiency over steel ones.
The
other weakness is something that may or may not manifest itself as
readily, depending on the circumstances and how often the watch is
serviced. This potential problem is easily understood by any watchmaker
who has serviced a lot of these movements. The problem is that the 2
setting wheels under the dial, and the two small and thin posts that
they pivot on, can be easily damaged if the lubrication runs dry. If
the grease on the canon pinion dries up due to age or moisture in the
watch case, the teeth on these small thin wheels will break off. The
more severe problem is if the lubrication on the posts runs dry, then
the first post will be worn away in no time at all, as shown in the
photo below. This is less of a problem on the second post as it is a
steel pin that is not riveted into the main plate. So it can be easily
replaced if it is worn or damaged. Unfortunately the first post is part
of the main plate, and is made of brass just like it. Therefore if this
post gets damaged like that, the only way to repair it is by replacing
the entire main plate. An expensive proposition at best. It’s worth
noting that this was not a problem on Rolex’s older caliber 3035
because the diameter of the post was quite a bit thicker, as was the
set wheel itself. Please note that this shouldn’t be a problem for
those who take care of their watches and have them serviced at regular
intervals – every four to five years as recommended by most factories
today. I am 100% in agreement with this recommended service interval.
Whether
Rolex is interested in making any more radical upgrades to this
movement is anybody’s guess, but my feeling is that by now they
probably have a replacement waiting in the wings for it. With the
economy being in the shambles that it’s in right now, the timing might
not be right just yet. Only time will tell. But hey, if anybody gets an
email from Bruno Meir about their new movement be a sport and tell your
friends on Time Zone about it.
Final
thoughts:
A short
note about Rolex’s latest innovations – their Parachrom hairspring and
Paraflex shock absorber.
I’m
not sure why Rolex went this route instead of going with silicone
hairsprings like the Swatch Group, JLC etc. This project is a joint
venture between Rolex and them, and with the money that they have
invested in it, they obviously have the same right as their partners to
use this technology. The only reason that I can proffer for them not
going with the silicone hairspring, is that they might be obliged to
give up using their Breguet overcoil in it.
As
an aside, most people aren’t aware of the many joint ventures that the
major Swiss watch companies undertake. From a financial point of view
it makes a lot of sense if one compares Intel’s R&D budget (or
even
a much smaller company like Apple) to Rolex’s, one will understand that
it makes a lot of sense to pool limited R&D resources with the
Swatch Group and Richemont etc.
Having
said that though I commend them most highly for finally coming up with
a 100% non-magnetic hairspring material. It’s also worth noting that in
most of the balance wheels fitted with the Parachrom hairspring that I
have seen, they have elected to use the brass Greiner collet instead of
their usual metal one. As I mentioned in my review of the 2235 I have a
preference for it because it is also 100% non-magnetic.
As
far as their new Paraflex shock absorber is concerned, there’s not much
I can say about it without putting it though its paces. And no, I have
no intention of dropping a $5,000 watch ten feet onto a concrete floor
in order to test its efficacy. Especially one that doesn’t belong to
me. I know that Rolex has done these tests, but I haven’t personally
witnessed them, or examined the watches afterwards. Only time will tell
if both their new hairspring and shock absorber are as good as what
they claim to be, but I can vouch for the non-magnetic capabilities of
the former. Of course if Rolex send me a sample to test, I’ll be more
than happy to do so for free!
Dissecting
the Helium Escape Valve:
In
the first photo you can see the disassembled helium escape valve placed
in order of how it fits together. On the left is the piston with its
“O” ring gasket. This moves out (i.e. to the left) if the pressure
inside the case exceeds the tension of the spring holding it in place.
Next is the body of the valve which screws into the watch case from the
outside via the slots on its right. The flat portion on the left where
the threads end accommodates a flat gasket. The spring rests inside the
body of the valve, and this ensures that it is water resistant even
without any pressure being exerted on the piston from the outside. Last
is a flat metal washer. This is firmly friction fitted to the right
hand side of the piston which is tapered in order to accommodate it.
The washer also provides a base for the spring to rest on, thereby
pulling the piston firmly to the right with enough pressure to squeeze
the gasket thus ensuring the water resistance of the valve.
The
second photo shows the piston and its “O” ring gasket on the left. On
the right is the body of the valve showing the recess that the piston
and its gasket fit into. The flat part of the piston and the valve
should be flush with the watch case when installed correctly.
This
is a simple and reliable over pressure relief valve that should perform
exactly as designed. The whole unit should be replaced, together with
all the other gaskets, every time the watch is serviced, in order to
ensure the water resistance of the case. My only minor criticism is
that the gaskets are regular nitrile rubber and not the superior longer
lasting Viton gaskets that Sinn is now using in their dive watches.
Viton is a synthetic rubber developed by Dupont. Although slightly less
flexible, it was developed to withstand high oxygen environments and
other hostile chemicals and gases that will deteriorate natural rubber
gaskets in short order.
